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71.
High salt (sodium chloride) consumption is an important determinant of high blood pressure and cardiovascular risk. According to World Health Organisation (WHO) statistics, over 80% of cardiovascular disease (CVD) deaths take place in low-and middle-income countries, and elevated blood pressure levels were a major cause of these CVD deaths in those countries.1 Lifestyle factors such as unhealthy diet, physical inactivity, tobacco use and harmful use of alcohol have been considered the most important behavioural risk factors for heart disease and stroke.2Among dietary factors, high salt intake has been the most strongly associated with raised blood pressure and increased risk of stroke and CVD.3 Therefore dietary sodium restriction has been recommended as a non-pharmacological approach to blood pressure lowering,4-6 and for the prevention and control of non-communicable diseases at the population level.7,8Cumulative evidence has shown that even a modest reduction in salt intake was associated with blood pressure lowering and therefore with a significant reduction in incidence of cardiovascular events.9-12 Furthermore, data from the most recent systematic review and meta-analyses has shown the benefit of lowering sodium intake in apparently healthy adults and children,13 and in both hypertensive and normotensive individuals, irrespective of gender and ethnic group.9Since hypertension is associated with CVD worldwide, a public health intervention to reduce high blood pressure must target the role of lifestyle, particularly reduced sodium intake.7 Therefore, several countries have initiated strategies to reduce dietary salt intake in the general population by a combination of various procedures such as public education, food labelling, and collaboration with the food industry to reduce the salt content of processed food.14Among sub-Saharan African countries, only Nigeria and South Africa have developed dietary guidelines regarding salt intake.15 Recently, the South African government implemented important specific legislation towards decreasing salt intake in the population by reducing sodium content of processed foods by industries.16 Therefore, the current public health recommendation is that countries should launch national initiatives to reduce the over-consumption of salt as part of non-communicable disease prevention and healthy nutrition policies for limiting salt intake to less than 5 g/day for the general population including children.7 Despite of this guideline, however, high sodium intake remains prevalent around the world, with average daily salt intake varying from 5 to 18 g/day per person.17Although processed foods have been found to be the principal source of excessive dietary salt intake,18 sources of dietary sodium vary largely worldwide and may be influenced by cultural context and dietary habits of the population.19 In sub-Saharan African countries experiencing demographic and epidemiological transition, the rapid rise in prevalence of CVD (chiefly hypertension) has been attributed to lifestyle change, including high dietary sodium intake.20,21 However, consistent data from studies on risk factors are lacking for the majority of these countries.With regard to Angola, available data from a cross-sectional study reported a high prevalence of multiple cardiovascular risk factors, such as hypertension, sedentary lifestyle, electrocardiographic left ventricular hypertrophy,22 and high rate of the metabolic syndrome23 in an apparently healthy middle-aged population of university public employees living in urban and peri-urban areas.Determining the level of sodium intake in the population is crucial to establish intervention strategies and policy on reduction of sodium intake. For medical students in particular, it is very important to assess their awareness regarding dietary salt intake, since they are the future providers of healthcare information for the counselling of people about the need to reduce salt consumption. The aim of this study was to determine salt intake and to assess the knowledge, attitude and behaviour regarding dietary salt among medical students.  相似文献   
72.
Study Type – Therapy (case series) Level of Evidence 4 What's known on the subject? and What does the study add? High‐grade prostate cancers are associated with poor disease‐specific outcomes. A proportion of these tumours produce little PSA. This study demonstrates that among Gleason 8–10 prostate cancers, some of the worst survival outcomes are associated with the lowest PSA levels.

OBJECTIVE

  • ? To assess outcomes of patients with Gleason score 8–10 prostate cancer (CaP) with a low (≤2.5 ng/mL) vs higher preoperative serum PSA levels.

PATIENTS AND METHODS

  • ? From 1983 to 2003, 5544 patients underwent open radical prostatectomy, of whom 354 had a Gleason 8–10 tumour in the prostatectomy specimen.
  • ? Patients were stratified according to preoperative PSA level into four strata: ≤2.5 ng/mL (n= 31), 2.6–4 ng/mL (n= 31), 4.1–10 ng/mL (n= 174), and >10 ng/mL (n= 118).
  • ? We compared biochemical progression‐free survival (PFS), metastasis‐free survival (MFS), and cancer‐specific survival (CSS) as a function of preoperative PSA level.

RESULTS

  • ? Patients with PSA level ≤2.5 ng/mL were more likely to have seminal vesicle invasion (P= 0.003).
  • ? On Kaplan–Meier survival analysis, patients with a PSA level ≤2.5 ng/mL had proportionately worse outcomes than their counterparts with higher PSA levels.
  • ? The 7‐year PFS in the PSA ≤2.5 ng/mL stratum was lower than those of the PSA 2.6–4 ng/mL and 4–10 ng/mL strata (36% vs 50 and 42%, respectively); however, the lowest 7‐year PFS was found in those with a PSA level >10 ng/mL (32%, P= 0.02).
  • ? Gleason score 8–10 tumours with a PSA level ≤2.5 ng/mL also tended to have the lowest 7‐year MFS (75, 93, 89 and 92% for PSA level ≤2.5, 2.6–4, 4.1–10 and >10 ng/mL, respectively, P= 0.2) and CSS (81, 100, 94 and 90% for PSA level ≤2.5, 2.6–4, 4.1–10 and >10 ng/mL, respectively, P= 0.3), although these differences were not statistically significant.
  • ? In the subset with palpable disease, Gleason grade 8–10 disease with PSA level ≤2.5 ng/mL also was associated with a worse prognosis.

CONCLUSIONS

  • ? In patients with Gleason grade 8–10 disease, a proportion of these tumours are so poorly differentiated that they produce relatively little PSA.
  • ? Patients with high‐grade, low‐PSA tumours had less favourable outcomes than many of those with higher PSA levels.
  相似文献   
73.
Study Type – Prognosis (cohort) Level of Evidence 2a What's known on the subject? and What does the study add? Men fail active surveillance for a variety of reasons; however, no single reliable biomarker has been found to date which will identify these men from the outset. We know that there are about 35 prostate cancer risk alleles which have been discovered to influence risk of prostate cancer, from large‐scale genome‐wide association studies. Some of these have been associated with aggressive prostate cancer. Nobody has examined the potential for these risk alleles to predict men who might fail active surveillance. This study adds to the growing evidence that single nucleotide polymorphisms may be able to identify men who have aggressive prostate cancers, and that this could be part of a risk algorithm used in active surveillance protocols.

OBJECTIVE

  • ? To assess whether the carrier status of 35 risk alleles for prostate cancer (CaP) is associated with having unfavourable pathological features in the radical prostatectomy specimen in men with clinically low risk CaP who fulfil commonly accepted criteria as candidates for active surveillance.

PATIENTS AND METHODS

  • ? We studied men of European ancestry with CaP who fulfilled the commonly accepted clinical criteria for active surveillance (T1c, prostate‐specific antigen <10 ng/mL, biopsy Gleason ≤6, three or fewer positive cores, ≤50% tumour involvement/core) but instead underwent early radical prostatectomy.
  • ? We genotyped these men for 35 CaP risk alleles. We defined ‘unfavourable’ pathological characteristics to be Gleason ≥7 and/or ≥ pT2b in their radical prostatectomy specimen.

RESULTS

  • ? In all, 263 men (median age 60 [46–72] years) fulfilled our selection criteria for active surveillance, and 58 of 263 (22.1%) were found to have ‘unfavourable’ pathological characteristics.
  • ? The frequencies of three CaP risk alleles (rs1447295 [8q24], P= 0.004; rs1571801 [9q33.2], P= 0.03; rs11228565 [11q13], P= 0.02) were significantly higher in men with ‘unfavourable’ pathological characteristics.
  • ? Two other risk alleles were proportionately more frequent (rs10934853 [3q21], P= 0.06; rs1859962 [17q24], P= 0.07) but did not achieve nominal statistical significance.
  • ? Carriers of any one of the significantly over‐represented risk alleles had twice the likelihood of unfavourable tumour features (P= 0.03), and carriers of any two had a sevenfold increased likelihood (P= 0.001).
  • ? Receiver–operator curve analysis demonstrated an area under the curve of 0.66, suggesting that the number of single nucleotide polymorphisms carried provided discrimination between men with ‘favourable’ and ‘unfavourable’ tumour features in their prostatectomy specimen.

CONCLUSION

  • ? In potential candidates for active surveillance, certain CaP risk alleles are more prevalent in patients with ‘unfavourable’ pathological characteristics in their radical prostatectomy specimen.
  相似文献   
74.
75.
Patterns of endoscopy use in the United States   总被引:7,自引:0,他引:7  
BACKGROUND & AIMS: The aim of this study was to use a large national endoscopic database to determine why routine endoscopy is performed in diverse practice settings. METHODS: A computerized endoscopic report generator was developed and disseminated to gastrointestinal (GI) specialists in diverse practice settings. After reports were generated, a data file was transmitted electronically to a central databank, where data were merged from multiple sites for analysis. RESULTS: From April 1, 1997, to October 28, 1998, 276 physicians in 31 practice sites in 21 states provided 18,444 esophagogastroduodenoscopy (EGD) reports, 20,748 colonoscopy reports, and 9767 flexible sigmoidoscopy reports to the central databank. EGD was most commonly performed to evaluate dyspepsia and/or abdominal pain (23.7%), dysphagia (20%), symptoms of gastroesophageal reflux without dysphagia (17%), and suspected upper GI bleeding (16.3%). Colonoscopy was most often performed for surveillance of prior neoplasia (24%) and evaluation of hematochezia (19%) or positive fecal occult blood test (15%). Flexible sigmoidoscopy was most commonly performed for routine screening (40%) and evaluation of hematochezia (22%). There were significant differences between academic and nonacademic sites. CONCLUSIONS: The endoscopic database can be an important resource for future research in endoscopy by documenting current practice patterns and changes in practice over time.  相似文献   
76.
Purpose: To review literature specific to the use of AAC with adults who have severe aphasia. Method: The authors reviewed studies involving AAC interventions for adults with severe aphasia. Results: Published data support the use of aided and unaided AAC with adults with severe aphasia in controlled treatment contexts. Reported gains in communication typically have not generalized to everyday settings. Conclusions: The application of AAC with persons with severe aphasia must address factors potentially limiting treatment success outside of training environments.  相似文献   
77.
78.
Telemedicine services are being increasingly used. Although insurers and other payers are covering some services in the USA, the rationale for these coverage decisions is not always evidence-based. We reviewed the literature for telemedicine services that substitute for face-to-face medical diagnosis and treatment. We focused on three types of telemedicine services: store-and-forward, home-based and office/hospital-based services. Studies were included if they were relevant to at least one of the three study areas, addressed at least one key question and contained reported results. We excluded articles that did not study a service requiring face-to-face encounters (i.e. teleradiology was excluded). Our search initially identified 4083 citations. After review, 597 were judged to be potentially relevant at the title/abstract level. Following a full-text review, 106 studies were included. Store-and-forward services have been studied in many specialties, the most common being dermatology, wound care and ophthalmology. The evidence for their efficacy is mixed. Several limited studies showed the benefits of home-based telemedicine interventions in chronic diseases. Studies of office/hospital-based telemedicine suggest that telemedicine is most effective for verbal interactions, e.g. videoconferencing for diagnosis and treatment in specialties like neurology and psychiatry. There are still significant gaps in the evidence base between where telemedicine is used and where its use is supported by high-quality evidence. Further well-designed research is necessary to understand how best to deploy telemedicine services in health care.  相似文献   
79.
80.
Worldwide patterns of combination drug usage   总被引:1,自引:0,他引:1  
Summary Two related and interlocking spheres of activity with respect to combination drugs, the sphere of theoretical debate and the sphere of actual use, must be considered. Debate and learned opinion serves to strengthen the scientific basis for the development and prescribing of combination drugs. Physician preferences and actual usage patterns around the world, among both specialists and general practitioners, show that combination therapy is considered good therapy in the majority of countries. An examination of the registration statistics for combinations vs. single entity drugs shows that combination drugs are welcome additions to therapy in an era of scientific sophistication and are acceptable under the scrutiny of today's modern review process.  相似文献   
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